Flu or Cold? Here's How You Can Tell Them Apart

Credit: Hatházi Szilvia via Flickr Credit: Hatházi Szilvia via Flickr

The flu season occurs in the fall and winter, and peaks in January or February. This is why you may have recently noticed a greater push to get vaccinated. It's very important because there are significant secondary illnesses, and even the possibility of death, associated with the Influenza virus infection.

However, it's not always easy to distinguish the flu from the common cold. To do so, look for the flu's primary identifiers, which are the presence of fever and length of the illness.

Flu virus infection is an attack of the respiratory system. It can occur in outbreaks or epidemics throughout the world, particularly in the winter months because people tend to be indoors more often and in close contact with one another. This makes the transmission of the virus much more likely as the spread is mainly person-to-person via sneezing, coughing or the transfer of germs from surfaces.

The current recommendation is that everyone six months and older be vaccinated.

In general, flu symptoms are more severe than the cold. The most typical symptoms associated with a flu virus infection are:

  • Fever (over 1000F - 1040F)
  • Headache and muscle aches
  • Fatigue
  • Cough and sore throat may also be present

Individuals suffering with the flu will often times remember when they became ill by the abruptness of their symptoms, as many victims describe the event as hitting them like a ton of bricks. Illness may last 2-to-5 days.

The common cold, caused by other viruses, last no more than one or two days and is not typically accompanied by a fever. If a fever is present it is generally low-grade (less than 1010F).

Most people with the flu will have a fever accompanied by muscle aches and pains, and additionally have cold-like symptoms (runny nose, sore throat). The symptoms typically get better over two to five days, but the illness itself may last a week or so longer.

Pneumonia is the most common and most dangerous complication of the flu virus infection. We see this most commonly in the very young or the very old, nursing home patients and people with chronic illnesses such as diabetes or heart/lung disease.

This infection is usually recognized and treated based on symptoms. Treatment is generally supportive (with fever/pain reducing medications, fluids and rest).

Now, when should you seek help if you have an infection? For the majority of cases, the recovery is between one and two weeks. That said, you should contact your doctor if you have the following symptoms:

  • Shortness of breath or trouble breathing
  • Pain or pressure in chest or stomach
  • Signs of dehydration (i.e. dizziness upon standing, or not urinating)
  • Confusion
  • Persistent vomiting or inability to drink fluids

For children, it's important to seek medical help if you notice:

  • Blue or purplish skin color
  • Irritability (not wanting to be held)
  • No tears when crying (in infants)
  • Fever with a rash
  • Not waking up easily

Speaking of children, let us take a moment to address when it is appropriate to treat fever in children.

Fever is the body s normal physiological response to most commonly infections (although there are a variety of other conditions that may cause fever). It can be very challenging for parents to know when to be concerned.

Let's start by defining fever:

  • Rectal temperature (the most accurate) above 100.40F
  • Oral temperature above 1000F
  • Axillary (armpit) temperature above 990F
  • Ear temperature above 100.40F
  • Forehead temperature above 100.40F

There are pros and cons when deciding to treat a fever. The physiological purpose of the fever is to fight an infection, however the child is in discomfort. The most important thing for a caregiver to recognize is not so much the height of the fever, but more the appearance of the child, or how the child behaves.

Most fevers can be safely treated at home, but you should contact your doctor for the following reasons:

  • Infants less than three months with a temperature greater than 100.40F (regardless of the appearance). No fever reducers should be given before a doctor is consulted
  • Children between three months and three years with a temperature greater than 100.40F for more than three days
  • Children between 3-and-36 months with temperature of 102 0F or greater
  • Any age child with temperature greater than 1030F
  • Any age child with febrile seizures
  • Any age child with fevers greater than seven days
  • Any age child with fever and chronic medical problem
  • Children with fever and new skin rash

Treatment for fevers in a child are usually supportive with fever and pain reducing medications, increase in fluids (fever can cause dehydration), and rest.